Lift installation



Dec. 14, 1965 l. v. K. HOTT LIFT INSTALLATION 2 Sheets-Sheet 1 FiledJune 8, 1962 INVENTOR. /0/\/ I//(- H0 TT IIIIIIIIIIIIIHH rill? HISflTTOEA/EYS JIE. Z

Dec. 14, 1965 v. K. HOTT 3,223,124

LIFT INSTALLATION Filed June 8, 1962 2 Sheets-Sheet 2 INVENTOR. IOA/ MKH077 BY AQW AM United States Patent Ohio Filed June 8, 1962, Ser. No.201,151 1 Uaim. (Cl. 137636.1)

This invention relates to a lift installation and more particularly tomeans for controlling the operation of a lift jacking unit.

An object of this invention is to provide a valve housing and controlstructure for a lift installation, the top of which is substantiallyflush with the floor in which the lift installation is mounted.

Another object of this invention is to provide a vehicle lift valvecontrol structure in which accidental operation of the valve isprevented.

Other objects and advantages reside in the construction of parts, thecombination thereof, the method of manufacture and the mode ofoperation, as will become more apparent from the following description.

Referring to the drawings:

FIGURE 1 is a schematic plan view of a lift installation made inaccordance with this invention.

FIGURE 2 is a schematic side elevational view of the lift installationof FIGURE 1.

FIGURE 3 is a perspective view of the top of a valve housing and controlstructure used in the installation in FIGURE 1.

FIGURE 4 is a transverse cross-sectional view of the housing and thecontrol structure mounted therein taken along line 44 of FIGURE 1.

FIGURE 5 is a longitudinal cross-sectional view taken along line 5-5 ofFIGURE 4 and illustrating a valve and its control structure in sideelevational view.

A lift installation made in accordance with this invention isillustrated in FIGURES l and 2 as comprising a vehicle lift includingthe usual jacking unit 12 embedded within a floor or support surface 14and a superstructure 16. The vehicle lift 10 is of the type known as aframe contact lift. In the recent past, such lifts have been made withrotatable arms and a variety of slides and pads so that the users of thelifts may easily position the pads where desired to safely engage andlift a motor vehicle. The jacking unit 12 may be of any conventionalhydraulic or semi-hydraulic type. In FIG- URE 2, a semi-hydraulic typeof jacking unit is shown utilizing an air line or tube 18 which passesthrough the floor 14, through the base of the jacking unit 12, and

3,223,124 Patented Dec. 14, 1965 "ice of the lift may kneel or bend downto properly position the various arms or pads as are required to safelyengage the vehicle and at the same time control the vertical movement ofthe lift superstructure 16. In this way, the user of the lift mayconstantly check to see that the vehicle frame engaging portions of thelift superstructure 16 remain properly positioned until fully engagedwith the vehicle frame.

In accordance with this invention, a control box 22 is embedded withinthe floor 14 adjacent the lift 10 as shown best in FIGURES l and 2. Theair line or tube 18 is connected to the control box 22 through a fitting23 mounted on the side of the box 22. A second air line or tube 24 isalso connected to the side of the control box 22 by a similar fitting 23and is directed to a source of air under pressure (not shown).

Referring to FIGURES 2 through 5, the control box 22 is illustrated ascomprising a generally rectangular housing 25 embedded within the floor14. A supporting framework 26 is welded to the top of the housing 25,the framework 26 comprising angle members placed in a rectangular arraysuch that the top surface of the framework 26 is flush with the topsurface of the floor 14. A square bead 28 is welded to the internal faceof the framework 26, providing a support for a top or cover plate 30which has a central, rectangular aperture 32 therein for receivingportions of a valve control structure described below. The top or coverplate 30 may be fixed in relation to the remainder of the box 22 bymeans of corner supports 34 welded to the bead 28, the corner supportsbeing apertured to receive screws 36 which also pass through alignedapertures in the corners of the cover plate 30. A drain pipe 38 may beconnected to the base of the box 22 to avoid accumulation of watertherein.

As shown in FIGURES 4 and 5, the box 22 houses an air valve structure50, the operation of which is coninto a piston 20. Upon introduction ofair under pressure into the piston 20, oil within the jacking unit 12 isforced downwardly through a metering structure (not shown) in the baseof the piston 20, causing the piston 20 and the superstructure 16 torise.

In the past, air under pressure has been introduced into the liftjacking unit from a source of air under pressure, such as an aircompressor, the passage of air being controlled by a valve membermounted considerably above the vehicle lift, normally on or adjacent avertical wall near the lift. Such location of the valve or controlstructure for controlling the passage of air to a lift jacking unit usedto be the most convenient since, in the past, a motor vehicle was merelydriven over or onto a vehicle lift, the control structure being operatedto elevate the vehicle. However, since present day frame contact liftsnormally must be positioned relative to the underbody of the vehicleafter the vehicle is driven over the lift, a control structure mountedwell above a floor, such as 14, is an inconvenience. In accordance withthis invention, the control structure is placed so that the operator oruser trolled by a novel valve operating mechanism 51 made in'accordancewith this invention. Since the valve 50 may be conventional, the detailsof construction thereof are not described herein. Briefly, the valve 50may be a poppet type valve including an air inlet section 52 and an airexhaust section 54. The inlet section 52 communicates with an air inletport 24a connected by its associated fitting 23 to the air line or tube24. A center port 18a is similarly adapted to be connected to thejacking unit line or tube 18. An exhaust port 56 is provided on the leftside of the casting forming the valve 50 as viewed in FIGURE 4. Ifdesired, a mufiler 57 may be provided to reduce the noise associatedwith exhausting air from the jacking unit 12.

The passage of air to and from the jacking unit 12 through the line 18is controlled by a pair of spring biased valve stems or plungers, namelyan air inlet plunger 58 and an air exhaust plunger 60. Both plungers 58and 60 are biased upwardly. Should the inlet plunger 58 be depressed,air under pressure will be forced through the port 18a and the line 18into the jacking unit 12. Similarly, should the exhaust plunger 60 bedepressed, air will be exhausted from the jacking unit 12 through theline 18 and the muffler 57 to atmosphere.

A cylindrical, upright, support rod 62, integral with the remainder ofthe valve 50, is located centrally thereof. The upper portion of the rod62 is slotted to provide a pair of opposed, upwardly projecting ears 64straddling a valve stem rocker arm 66 which is mounted for pivotalmovement about a horizontal axis by a rocker arm pivot pin 68 passingcentrally through the support rod 62. The valve stem rocker arm 66 is ofa conventional type having opposed lower surfaces, designated 70,adapted to engage the valve stems or plungers 58, 60 to control theoperation of the valve 50. The upper, arcuate surface of the rocker arm66 is generally concave and is adapted to be engaged by opposed,depending arms 74 forming part of a treadle 76 mounted for rotationabout a horizontal axis upon the ears 64 by means of a treadle pivot pin78. It will be noted in FIGURE 5 that the axes of rotation of the rockerarm 66 and the treadle 76 are parallel. Accordingly, pivotal movement ofthe needle 76 in a clockwise direction, as v'iwed in FIGURE 4, causesthe rocker arm 66 to similarly pivot in a clockwise direction forcingthe inlet valve stem or plunger 58 downwardl Counter= clockwise rotationof the treadle 76 as viewed in FIGURE 4 likewise forces the exhaust stemor plunger 60 downwardly.

Movement of the treadle 76 is controlled in accordance with thisinvention by a treadle control handle, generally designated 80, havingan elongated rod portion 82 and a hollow, cylindrical knob portion 84connected to the top of the rod portion 82. The rod portion 82 is shownas generally rectangular in cross-section and is received for verticalsliding movement within a rectangular bore 86 formed at an inclinedangle in the body of the treadle 76. As shown best in FIGURE 5, the bore86 projects between the upper surface of the treadle 76 and a flaredside portion thereof;

Normally, the lno b portion 84 rests on top of the treadle 76 as shownin full lilies iii 3 and in FIGURES 4 and 5. As illustrated in FIGURE 3,however, the knob portion 84 may be pulled upwardly whereupon the rodportion 82 moves vertically through the bore 86. Dotted lines 80a inFIGURE 3 represent the position of the handle 80 when first pulledupwardly and is a neutral position for the control structure, neitherplunger 58 nor 60 being actuated thereby. Should the handle 80 be movedto the right as viewed in FIGURE 3 into the dotted line position 80b,the inlet stem or plunger 58 is depressed, whereupon air under pressurewill be introduced to the jacking unit to raise the superstructure 16.Movement of the control handle 80 into the dotted line position 800shown in FIGURE 3 exhausts air from the jacking unit through the muffler57 to lower the superstructure 16. As a safety measure, the controlhandle 80 does not lock in either the right or left positions 8011 or800. Rather, should the handle 80 be released, it will always return toits central or neutral position 80a due to the bias on the plungers 58and 60.

It will be observed that the handle 80 passes through the aperture 32within the cover plate 30 and a protective shell or frame asembly 90 iswelded within the aperture 32 in surrounding relation to the handle 80.The assembly 90 may include a pair of side plates 92 welded to the coverplate along the sides of the aperture 32 and connected together by apair of end plates 94. To avoid interference between the treadle 76 andthe shell or frame assembly 90, the top surface, designated 98, of thetreadle 76 is generally semi-circular so that it may pivot through itscomplete range of movement without engaging any portion of the assembly90. Since the handle 80 is inclined to the vertical, the knob portion 84thereof, when in its normal lowered position, is located adjacent one ofthe side plates 92. A pair of locking ears or lugs 96 are connected, asby welding, to such side plate 92 in straddling relation to the knobportion 84.

In operation, as previously noted, the handle member 80 normally is inits lower position shown in full lines in FIGURE 3. When in thisposition, the locking cars 96 prevent rotation of the handle 80 and,accordingly, of the treadle 76. This is an important feature of thisinvention. Normally, there is considerable traffic along the floorsofservice stations or garages where lift installations are placed.Accordingly, it is necessary to prevent accidential operation of thelift through movement of the treadle 76 should a service stationattendant accidentally step on the handle 80 or should a vehicle bedriven over the control box 22. Since the knob portion 84 of the handle80 projects only slightly above the, floor 14, there I is substantiallyno obstruction to the normal use of the floor. Note that the knobportion 84 is generally elongate so that it will be firmly held betweenthe locking ears 96. However, the rod portion 82 of the handle isconsiderably smaller in cross-section and will not contact the lockingears 96 during operation of the control handle 80. To prevent removal ofthe handle 80 from the treadle 76, the lower portion thereof may beprovided with a spring roll pin 100 passing through a transverseaperture therein, which pin is sufficiently long to provide a stop forengagement with the body of the treadle 76.

Since the knob portion 84 may be made hollow as described hereln, it canbe engaged and actuated by a hook on the end of a conventionalpositioning rod used with vehicle lift superstructures. Hence, it isunnecessary for the operator to be in a kneeling position to actuate thehandle 80. Most importantly, however, the operator can be in a kneelingposition to keep close watch on the position of the vehicle frameengaging portions of the superstructure 16 while simulaneously actuatingthe control handle 80.

It is thus seen that the objects of the invention have been met by theprovision of a control structure which may be mounted such that its topsurface is substantially flush with the floor or other surface uponwhich a vehicle lift is to be operated. The structure is quite simpleand efficient in operation. It uses a conventional valve 50 operated bythe normal valve rocker arm 66 and a treadle member 76 which may be arelatively simple casting. The housing 25 may be made from inexpensivesheet metal and installed when the floor 14 is initially formed. Sincealmost the entire structure is covered by the cover plate 30, which isflush with the top surface of the top of the floor 14, the control box22 and its associated valve control structure does not interfere withthe normal traffic on the floor 14. It should be noted that the assemblyprovides an opening whereby the arcuate top surface 98 of the treadle 76may be inspected. For convenience, the treadle may be marked with arrowsand designations such as UP and DN indicating the direction of liftmovement by operation of the control handle 80.

Although the control structure of this invention is disclosed inassociation with a semi-hydraulic lift, the invention is not necessarilyso limited. With little modification, the various portions of thecontrol structure could be used with any type of fluid actuator.

Although the presently preferred embodiment of the device has beendescribed, it will be understood that within the purview of thisinvention various changes may be made in the form, details, proportionand arrangement of parts, the combination thereof and mode of operation,which generally stated consist in a device capable of carrying out theobjects set forth, as disclosed and defined in the appended claim.

Having thus described my invention, I claim:

In a vehicle lift control structure, the combination comprising: ahousing; an aperture cover plate mounted on said housing; a fluid valvemounted within said housing, said valve having an inlet section and anoutlet section and including a pair of valve actuating plungers, one foreach section; valve operating means including a valve stem rocker armmounted upon said valve for pivotal movement about a horizontal axisadjacent said plungers, said rocker arm having surfaces adapted toengage and actuate said plungers upon pivotal movement thereof, atreadle mounted for pivotal movement upon said valve about a horizontalaxis parallel to the axis of rotation of said rocker arm, said treadlehaving a pair of opposed arms adapted to engage and pivot said rockerarm and further having a bore extending therethrough along an axisextending at an inclined angle to the horizontal, a treadle controlhandle having an elongate rod portion mounted for slidable movementwithin said bore and a knob portion connected to the top of said rodportion, whereby said control handle may be raised for manual operationto pivot said treadle or be lowered to a position wherein said knobportion lies closely adjacent the plane of the top of said cover plateand said elongate rod portion depends into said housing; and lock meansconnected to said cover plate extending in the path of said controlhandle and engaging said knob portion when said handle is lowered toreleasably lock said handle in a predetermined position wherebyaccidental operation of said control handle is prevented.

4/1924 Beerworth. 9/1933 Pelouch.

6 Cochin.

Hott et al 187-636 Hott et a1 1874.41

Couse 74566 X Hott et al. 137-622 La Karnafeaux et al. 187--8.41

FOREIGN PATENTS Great Britain.

SAMUEL F. COLEMAN, Primary Examiner.

ANDRES H. NIELSEN, Examiner.

